Bug 1545823 - Implement non-standard CSSStyleSheet.rules, CSSStyleSheet.addRule and CSSStyleSheet.removeRule. r=bzbarsky

It's not worth dying on this hill. Both Blink and WebKit pass the tests.

(Well, WebKit actually fails one of the latest ones I wrote, cssRules and rules
are not the same JS object, WebKit returns a new rule list. I'll file)

Spec PR in https://github.com/w3c/csswg-drafts/pull/3900.

Differential Revision: https://phabricator.services.mozilla.com/D30348

--HG--
extra : moz-landing-system : lando

dom/webidl/CSSStyleSheet.webidl

@@ -24,4 +24,12 @@ interface CSSStyleSheet : StyleSheet {
   unsigned long insertRule(DOMString rule, optional unsigned long index = 0);
   [Throws, NeedsSubjectPrincipal]
   void deleteRule(unsigned long index);
+
+  // Non-standard WebKit things.
+  [Throws, NeedsSubjectPrincipal, BinaryName="cssRules"]
+  readonly attribute CSSRuleList rules;
+  [Throws, NeedsSubjectPrincipal, BinaryName="deleteRule"]
+  void removeRule(optional unsigned long index = 0);
+  [Throws, NeedsSubjectPrincipal]
+  long addRule(optional DOMString selector = "undefined", optional DOMString style = "undefined", optional unsigned long index);
 };

layout/style/StyleSheet.cpp

@@ -510,10 +510,7 @@ css::Rule* StyleSheet::GetDOMOwnerRule() const { return mOwnerRule; }
 uint32_t StyleSheet::InsertRule(const nsAString& aRule, uint32_t aIndex,
                                 nsIPrincipal& aSubjectPrincipal,
                                 ErrorResult& aRv) {
-  if (IsReadOnly()) {
-    return 0;
-  }
-  if (!AreRulesAvailable(aSubjectPrincipal, aRv)) {
+  if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
     return 0;
   }
   return InsertRuleInternal(aRule, aIndex, aRv);
@@ -521,15 +518,36 @@ uint32_t StyleSheet::InsertRule(const nsAString& aRule, uint32_t aIndex,
 
 void StyleSheet::DeleteRule(uint32_t aIndex, nsIPrincipal& aSubjectPrincipal,
                             ErrorResult& aRv) {
-  if (IsReadOnly()) {
-    return;
-  }
-  if (!AreRulesAvailable(aSubjectPrincipal, aRv)) {
+  if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
     return;
   }
   return DeleteRuleInternal(aIndex, aRv);
 }
 
+int32_t StyleSheet::AddRule(const nsAString& aSelector, const nsAString& aBlock,
+                            const Optional<uint32_t>& aIndex,
+                            nsIPrincipal& aSubjectPrincipal, ErrorResult& aRv) {
+  if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
+    return -1;
+  }
+
+  nsAutoString rule;
+  rule.Append(aSelector);
+  rule.AppendLiteral(" { ");
+  if (!aBlock.IsEmpty()) {
+    rule.Append(aBlock);
+    rule.Append(' ');
+  }
+  rule.Append('}');
+
+  auto index =
+      aIndex.WasPassed() ? aIndex.Value() : GetCssRulesInternal()->Length();
+
+  InsertRuleInternal(rule, index, aRv);
+  // Always return -1.
+  return -1;
+}
+
 nsresult StyleSheet::DeleteRuleFromGroup(css::GroupRule* aGroup,
                                          uint32_t aIndex) {
   NS_ENSURE_ARG_POINTER(aGroup);

layout/style/StyleSheet.h

@@ -346,6 +346,9 @@ class StyleSheet final : public nsICSSLoaderObserver, public nsWrapperCache {
                       nsIPrincipal& aSubjectPrincipal, ErrorResult& aRv);
   void DeleteRule(uint32_t aIndex, nsIPrincipal& aSubjectPrincipal,
                   ErrorResult& aRv);
+  int32_t AddRule(const nsAString& aSelector, const nsAString& aBlock,
+                  const dom::Optional<uint32_t>& aIndex,
+                  nsIPrincipal& aSubjectPrincipal, ErrorResult& aRv);
 
   // WebIDL miscellaneous bits
   inline dom::ParentObject GetParentObject() const;

testing/web-platform/meta/css/css-counter-styles/idlharness.html.ini

@@ -2,45 +2,3 @@
   [css-counter-styles IDL tests]
     expected: FAIL
 
-  [CSSCounterStyleRule interface: counter must inherit property "speakAs" with the proper type]
-    expected: FAIL
-
-  [Stringification of counter]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "symbols" with the proper type]
-    expected: FAIL
-
-  [CSSRule interface: counter must inherit property "COUNTER_STYLE_RULE" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule must be primary interface of counter]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "pad" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "prefix" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "suffix" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "name" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "fallback" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "negative" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "additiveSymbols" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "range" with the proper type]
-    expected: FAIL
-
-  [CSSCounterStyleRule interface: counter must inherit property "system" with the proper type]
-    expected: FAIL
-

testing/web-platform/meta/css/css-typed-om/the-stylepropertymap/declared/declared.tentative.html.ini

@@ -2,3 +2,24 @@
   [Declared StylePropertyMap tests]
     expected: FAIL
 
+  [Declared StylePropertyMap contains custom property declarations]
+    expected: FAIL
+
+  [Declared StylePropertyMap contains properties with their last valid value]
+    expected: FAIL
+
+  [Declared StylePropertyMap does not contain properties with invalid values]
+    expected: FAIL
+
+  [Declared StylePropertyMap only contains properties in the style rule]
+    expected: FAIL
+
+  [Declared StylePropertyMap is live]
+    expected: FAIL
+
+  [Declared StylePropertyMap does not contain inline styles]
+    expected: FAIL
+
+  [Declared StylePropertyMap contains CSS property declarations in style rules]
+    expected: FAIL
+

testing/web-platform/tests/css/cssom/CSSStyleSheet.html

@@ -38,6 +38,32 @@
         assert_equals(styleSheet.cssRules[2], undefined, "CSSStyleSheet cssRules attribute after deleteRule function");
         assert_equals(styleSheet.cssRules[0].randomProperty, 1, "[SameObject] cssRules attribute after deleteRule function");
         assert_equals(styleSheet.cssRules[1].randomProperty, 2, "[SameObject] cssRules attribute after deleteRule function");
+
+        styleSheet.removeRule();
+        assert_equals(styleSheet.cssRules.length, 1, "CSSStyleSheet cssRules attribute after removeRule function");
+        assert_equals(styleSheet.cssRules[0].cssText, "#foo { height: 100px; }", "CSSStyleSheet cssRules attribute after removeRule function");
+
+        assert_equals(styleSheet.addRule("@media all", "#foo { color: red }"), -1);
+        assert_equals(styleSheet.cssRules.length, 2, "CSSStyleSheet cssRules attribute after addRule function");
+        assert_true(styleSheet.cssRules[1] instanceof CSSMediaRule, "CSSStyleSheet addRule does some silly string concatenation");
+
+        styleSheet.removeRule(1);
+        assert_equals(styleSheet.cssRules.length, 1, "CSSStyleSheet cssRules attribute after removeRule function with index");
+        assert_equals(styleSheet.cssRules[0].cssText, "#foo { height: 100px; }", "CSSStyleSheet cssRules attribute after deleteRule function with index");
+
+        assert_equals(styleSheet.addRule("#foo", "color: red"), -1);
+        assert_equals(styleSheet.cssRules.length, 2, "CSSStyleSheet cssRules attribute after addRule function with simple selector");
+        assert_equals(styleSheet.cssRules[1].cssText, "#foo { color: red; }", "CSSStyleSheet cssRules attribute after addRule function without index appends to the end");
+
+        assert_equals(styleSheet.addRule("#foo", "color: blue", 0), -1);
+        assert_equals(styleSheet.cssRules.length, 3, "CSSStyleSheet cssRules attribute after addRule function with simple selector with index");
+        assert_equals(styleSheet.cssRules[0].cssText, "#foo { color: blue; }", "addRule function with index performs an insertion");
+
+        assert_equals(styleSheet.addRule(), -1);
+        assert_equals(styleSheet.cssRules.length, 4, "CSSStyleSheet cssRules attribute after addRule function without arguments");
+        assert_equals(styleSheet.cssRules[3].cssText, "undefined { }", "addRule arguments default to undefined");
+
+        assert_equals(styleSheet.cssRules, styleSheet.rules, "CSSStyleSheet.rules returns the same object as CSSStyleSheet.cssRules");
     });
     </script>
 </head>